基于单片机的便携式空气质量检测仪设计

基于单片机的便携式空气质量检测仪设计(论文11700字)
摘要：本文主要介绍了基于单片机的便携式空气质量检测仪的设计和实现过程。该系统以STC90C51单片机为核心搭建硬件平台，具备对封闭空间内的甲醛、苯、甲苯等有害气体的采集、检测及显示功能。系统采用了体积小、重量轻、功耗低的传感器来采集数据；选用点阵式液晶屏LCD1602来显示数据，提供优良的人机交流页面；选用集成稳压电源7805供电，具有良好的便携性和通用性；同时还设计了声光报警系统，良好地实现当有毒气体浓度超出阈值时发出声光警报。该系统电路简单、精度高、实时性好，能够满足实际的需求。
关键词：STC90C51; 空气质量检测；有害气体

Single Chip Based Portable Air Quality Detector
Abstract: This paper mainly introduces the design and realization process of portable air quality detector based on single chip. This system builds hardware platform with the key of single chip STC90C51, and owns the functions of collecting, detecting and displaying the information of formaldehyde, benzeneand toluene in enclosed space. This system uses a sensor with small size, light weight and low power consumption to collect data. It chooses the dot-matrix LCD, i.e. LCD1602, to display data, which is an excellent man-machine dialogue interface. It is powered by integrated-circuit voltage regulator 7805, and thus has good versatility and portability. The sound and light alarm system is also designed to realize the alarms when the harmful gas concentration exceeds the threshold value. The system has simple circuit, high precision and good real-time performance.
Keywords: STC90C51; air quality detector; harmful gas
 

目录
1 绪论    1
1.1 研究背景    1
1.2 国内外研究现状    2
2 系统总体设计    3
2.1 系统总体结构    3
2.2 STC90C51单片机简介    4
2.3 MS1100气体传感器    5
2.4 ADC0809模数转换芯片    5
2.5 74LS74四分频芯片    6
2.6 LCD1602液晶显示屏    7
2.7 集成稳压电源7805    8
3 系统硬件设计    8
3.1 时钟电路    8
3.2 复位电路    9
3.3 气体传感器接口电路    9
3.4 四分频电路    11
3.5 模数转换电路    11
3.6 键盘电路    12
3.7 声光报警电路    13
3.8 显示电路    13
3.9 电源电路    15
4 系统软件设计    15
4.1 编程的语言选择    15
4.2 软件系统功能需求    15
4.3 软件系统设计    16
4.3.1 主程序流程    16
4.3.2 设置流程    16
4.3.3 气体浓度采集和显示流程    16
4.3.4 模数转换流程    17
5 系统测试    18
6 结束语    20
参考文献    21
致谢    22